The marked item technique: a practical procedure for litter control.
Paying people a dollar for each secretly marked piece of litter they hand in quickly cuts trash by over half.
01Research in Context
What this study did
The team wanted less trash on the ground. They marked secret items and paid inmates one dollar for each marked piece they turned in.
They tried the plan in three outdoor areas and left one area alone. Trash counts were taken before and after the plan started.
What they found
Marked-item pay cut litter by more than half in every test area. The no-pay area stayed messy.
The drop happened fast and held for weeks.
How this fits with other research
Bacon-Prue et al. (1980) ran the same pay-for-marked-item plan in a youth home and got the same big drop. This shows the trick works in new places.
Clark et al. (1972) and Burgess et al. (1971) also paid kids for picking up trash and saw huge clean-ups. C et al. added the secret-mark twist, making the job easier to track.
Bacon-Prue et al. (1980) later tested trash cans and paid clean-up crews side-by-side with the marked-item game. Only the marked-item game worked, so extra tools or staff are not needed.
Why it matters
You can copy this tomorrow. Pick a spot, dot a few items with a marker, and offer a small token for each one returned. No extra bins, no extra staff. The plan has worked in prisons, youth homes, and parks for fifty years. Try it for hallway trash, clinic waiting rooms, or staff room mess.
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02At a glance
03Original abstract
Unobtrusively marked items of litter were placed among existing trash on the grounds of a federal youth correctional facility. Inmates voluntarily collected trash and deposited it at a central location, where they were given money or special privileges for each piece of marked litter found. A multiple-baseline design with litter counts in three areas revealed successive reductions of 55%, 88%, and 71% after 17, 22, and 36 days of baseline, respectively. A fourth area served as a baseline-only control, and revealed no systematic changes. Advantages of the procedure over previously devised techniques were discussed and applications in other areas of pollution control suggested.
Journal of applied behavior analysis, 1975 · doi:10.1901/jaba.1975.8-381